Battens disease is one of the ceroid lipofuscinoses, characterized by juvenile onset of visual loss, seizures, and mental detrioration. The disease is characterized by autofluorescent pigment deposition in lysosomal structures. The gene for Battens disease (CLN3) was cloned by positional cloning - it appears to be a transmembrane protein located in the golgi. We have created a mouse with a deletion mutation in Cln3, the mouse ortholog to the human gene. These mice develop pigment deposition as is seen in affected humans. Studies are ongoing to determine if any of the other phenotypic abnormalities seen in Battens disease patients also develop in the mice. - Brain Disorders, Batten's Disease, Neurodegenerative